Inconel 625 Pipe & TubeASTM B444 UNS N06625 · Manufacturer, stockist & exporter, India
Also sold as Alloy 625 · UNS N06625 · W.Nr 2.4856 · Nicrofer 6020
Inconel 625 pipe is supplied seamless to ASTM B444 and welded to ASTM B705, in ASME pipe sizes and schedules, with tube to ASTM B444 · B704. It is a nickel–chromium–molybdenum alloy with niobium, chosen for seawater, high strength and high temperature in one alloy. Kanak Steel & Engineering Co. supplies it with EN 10204 3.1 mill certificates from Mumbai to buyers across India, the Gulf, South-East Asia, South America, Europe, the UK and the USA.
- Stock & mill supply
- EN 10204 3.1 / 3.2
- PMI on request
- NACE MR0175 on request
- Export packing
Reviewed by the Kanak Steel & Engineering Co. technical team · Updated October 2026
What is Inconel 625 Pipe & Tube?
Inconel 625 pipe & tube is a nickel–chromium–molybdenum alloy with niobium supplied as pipe & tube to ASTM B444 (UNS N06625). Buyers specify it for seawater, high strength and high temperature in one alloy. It is also sold as Alloy 625, UNS N06625, W.Nr 2.4856.
- What it is
- Nickel–chromium–molybdenum alloy with niobium
- Seamless
- ASTM B444
- Welded
- ASTM B705
- Sizes
- NPS ⅛" – 24" · OD tube to order
- Schedules
- 5S · 10S · 40S · 80S · 160 · XXS
- Best at
- Seawater, high strength and high temperature in one alloy
Inconel 625 Pipe & Tube Specification & Sizes
| Seamless pipe | ASTM B444 |
|---|---|
| Welded pipe | ASTM B705 |
| Tube | ASTM B444 · B704 |
| Grade | Inconel 625 · UNS N06625 · W.Nr 2.4856 |
| Size & schedule | NPS ⅛" to 24" to ASME B36.19 / B36.10; OD × wall for tube |
| Length | Single random, double random, or cut lengths |
| Ends | Plain end · bevelled end (for welding) · threaded |
| Testing | Hydrostatic or eddy-current · PMI · flattening & flaring · IGC on request |
| Documents | EN 10204 3.1 · 3.2 with third-party inspection |
Inconel 625 Pipe: Seamless, Welded or Tube?
Three different specifications cover 625 tubular products. Pick the route first — it decides price, test requirements and lead time. General requirements (tolerances, hydrostatic or electric testing) come from ASTM B829 (seamless) and B775 (welded). Schedules, the −12.5% wall tolerance and the B31.3 wall formula are explained in the pipe guide.
- Seamless pipe is ASTM B444; welded pipe is B705.
- B444 has two conditions: Grade 1 (annealed) for corrosion service and strength, and Grade 2 (solution annealed) for high-temperature creep service — state which.
- Matching filler is ERNiCrMo-3.
| Route | Specification | Use it for |
|---|---|---|
| Seamless pipe | ASTM B444 | Pressure and critical service; no weld seam to inspect. |
| Welded pipe | ASTM B705 | Economical in larger diameters and thinner walls where the code allows it. |
| Tube | ASTM B444 · B704 | Heat exchangers and instruments; ordered by exact OD × wall. |
Inconel 625 Pipe Wall & Weight by Schedule
For the same size, the schedule sets the wall — and the weight you pay for. Cross-sections are drawn to scale for 2" NPS (OD 60.33 mm, ASME B36.19); weights use the density of Inconel 625, 8.44 g/cm³.
Other sizes: pipe schedule chart and weight calculator.
Inconel 625 Pipe & Tube Chemical Composition
Under technical review for TDS.
| Element | Current requirement |
|---|---|
| Nickel | As specified |
| Chromium | As specified |
| Molybdenum | As specified |
| Niobium + Tantalum | As specified |
| Iron | As specified |
| Carbon | As specified |
| Manganese | As specified |
| Silicon | As specified |
| Titanium | As specified |
| Aluminium | As specified |
Numerical specification requirements are published only after the applicable current standard edition has been verified. Governing specification to be verified: ASTM B443 for UNS N06625.
Inconel 625 Pipe & Tube Mechanical Properties
Under technical review for TDS.
| Property | Current requirement |
|---|---|
| Tensile strength | As specified |
| Yield strength 0.2% | As specified |
| Elongation | As specified |
Numerical specification requirements are published only after the applicable current standard edition has been verified. Governing specification and condition to be verified: ASTM B443 for UNS N06625 — Grade 1 annealed plate.
Density & Physical Properties
| Property | Value |
|---|---|
| Density | 8.44 g/cm³ |
| Melting range | 1290 – 1350 °C |
| Magnetic | Non-magnetic |
| PREN (approx.) | ≈ 51 |
Inconel 625 Equivalent Grades
Inconel 625 Pipe Weight Chart (kg/m)
Weight per metre (kg/m) = (OD − WT) × WT × 0.02652, with OD and wall thickness in mm. The factor comes from Inconel 625's density of 8.44 g/cm³.
Example: 4" Sch 40S (114.30 × 6.02 mm)
(114.30 − 6.02) × 6.02 × 0.02652 = 17.28 kg/m
| NPS | OD mm | Sch 10S kg/m | Sch 40S kg/m |
|---|---|---|---|
| ½" | 21.34 | 1.08 | 1.36 |
| 1" | 33.40 | 2.25 | 2.69 |
| 2" | 60.33 | 4.23 | 5.85 |
| 3" | 88.90 | 6.94 | 12.14 |
| 4" | 114.30 | 9.00 | 17.28 |
| 6" | 168.28 | 14.86 | 30.38 |
| 8" | 219.08 | 21.47 | 45.74 |
Six-digit Harmonized System heading (nickel alloy, chapter 75). Your country adds its own digits — confirm with your customs broker. All HS codes.
How to Verify Inconel 625 Pipe & Tube with PMI
Positive material identification with a handheld XRF gun confirms the alloy on the piece itself, in seconds, before it is cut or welded. Inconel 625 is most often mixed up with Hastelloy C276 — the table shows which elements tell them apart.
Handheld XRF does not measure carbon or nitrogen; those come from the mill certificate or optical emission (OES) testing. PMI can be arranged on request — state it on your enquiry.
Under technical review for TDS.
| Element | Inconel 625 | Hastelloy C276 |
|---|---|---|
| Nickel | As specified | As specified |
| Chromium | As specified | As specified |
| Molybdenum | As specified | As specified |
| Titanium | As specified | — |
| Niobium | As specified | — |
| Tungsten | — | As specified |
| Iron | As specified | As specified |
| Manganese | As specified | As specified |
Inconel 625 Pipe & Tube Price — What Decides It
Two quotes for "625 pipe & tube" can differ by 20% and both be fair. We quote 625 pipe & tube per kg for full sizes and per piece for cut sizes. These six things move the price per kg, so you can compare offers like for like.
Inconel 625 Pipe & Tube Applications
Inconel 625 is specified when the cheaper grade will not survive the service but a higher alloy would be more than the job needs. These are the jobs our buyers use it for.
Inconel 625 Pipe & Tube vs 825, 2507 and C276
| Grade | Pipe & Tube standard | PREN (approx.) | Pick it when |
|---|---|---|---|
| Inconel 825 | ASTM B423 | ≈ 31 | Sulphuric and phosphoric acid service, chloride stress-corrosion cracking and sour gas |
| Super Duplex 2507 | ASTM A790 | ≈ 42 | Seawater and high-chloride service where strength also matters |
| Inconel 625 | ASTM B444 | ≈ 51 | Seawater, high strength and high temperature in one alloy |
| Hastelloy C276 | ASTM B622 | ≈ 68 | The most aggressive mixed acids, wet chlorine and hypochlorite |
PREN = Cr + 3.3 Mo + 16 N, from mid-range chemistry. A screening guide, not a substitute for corrosion data on your medium.
Inconel 625 Corrosion Resistance — Element by Element
Each alloying addition has a job. Knowing which one protects against your medium is the quickest way to judge whether 625 fits.
About 9% molybdenum gives PREN above 50 — seawater pitting is rarely a concern.
Niobium strengthens the matrix without heat treatment.
High nickel makes it virtually immune to chloride stress-corrosion cracking.
Keeps useful strength and oxidation resistance at high temperature.
How your 625 pipe & tube order runs
- 01Enquiry review — we confirm size, standard edition and documents against your MR or drawing.
- 02Heat selection & PMI — the mill certificate is checked against your order; PMI before processing is available on request.
- 03Processing — cutting, machining or bevelling to your specification, with heat numbers marked.
- 04Inspection — your third-party inspector witnesses, or we share photos and test reports.
- 05Packing & dispatch — seaworthy packing from Nhava Sheva (JNPT), Mumbai, FOB or CIF, documents sent before the vessel sails.
Standards on this page
Welding & Fabricating Inconel 625 Pipe & Tube
Inconel 625 welds by all common arc processes. A few points our buyers ask about:
| Matching filler | ERNiCrMo-3 (AWS A5.14) |
|---|---|
| Over-alloyed filler | ENiCrMo-3 electrode |
| Preheat | Not required; keep interpass temperature low |
| Cutting | Thermal or abrasive cutting; grind off heat-tinted edges before welding |
Follow your approved WPS; this is general guidance. See also 625 fittings and 625 flanges for the matching pipe-system parts.
How to Order Inconel 625 Pipe & Tube: RFQ Checklist
Get an accurate quote the first time. Copy this list into your enquiry:
- Seamless or welded, and the standard
- NPS and schedule (or OD × wall for tube)
- Length — random or cut, and number of lengths
- End finish — plain, bevelled or threaded
- Certificate type and extra tests
- Delivery port, Incoterm and required date
Inconel 625 pipe & tube for export
FOB / CIF · Nhava Sheva (JNPT), MumbaiInconel 625 pipe & tube — questions buyers ask
Is Inconel 625 the same as Alloy 625?
Alloy 625, UNS N06625, W.Nr 2.4856 are names used for Inconel 625 (W.Nr / EN numbers and older UNS variants are the closest designations; their limits can differ slightly, so specify the UNS number and ASTM grade on the order), and pipe & tube is ordered to ASTM B444 whichever name is on the enquiry.
What is the difference between Inconel 625 pipe and tube?
Pipe is ordered by nominal pipe size and schedule, for carrying fluids. Tube is ordered by exact outside diameter and wall, for heat exchangers and instruments, and is held to tighter tolerances.
Seamless or welded Inconel 625 pipe — which should I buy?
Seamless (ASTM B444) is the default for pressure and critical service. Welded (ASTM B705) is cheaper in larger diameters and thinner walls and is accepted where the design code allows it.
What is the wall-thickness tolerance on Inconel 625 pipe?
Seamless pipe is normally allowed −12.5% on nominal wall under its general-requirements standard (ASTM B829 (seamless) and B775 (welded)). Allow for it in the pressure calculation or order on minimum wall.
Can Inconel 625 pipe be welded to carbon-steel pipe?
Yes, with the right filler: a nickel-base filler such as ERNiCr-3 (or ERNiCrMo-3) is used when joining it to carbon steel. Follow a qualified WPS.
Can Inconel 625 pipe & tube be supplied to NACE MR0175?
Inconel 625 is covered by NACE MR0175 / ISO 15156-3 within the environmental limits, heat-treatment conditions and hardness limits that standard sets for it. State the requirement on the order so that condition and hardness are verified and reported on the certificate.
Inconel 625 or Hastelloy C276 — which should I choose?
Inconel 625 is chosen for seawater, high strength and high temperature in one alloy. Hastelloy C276 is the step up when you need more pitting resistance or strength. See the comparison table on this page, or ask us with your process conditions.
Sources: the ASTM / ASME specifications named on this page and producer datasheets · Last updated October 2026